Midges!
My first trip to Scotland - a hot and muggy early July. Trip leader warned us to bring midge repellant, head nets etc etc.
I was vocally contemptuous: ‘you pathetic Brits! I grew up in darkest Africa, feasted on by mosquitoes, tse tse flies and all manner of terrible beasts the like of which you can only imagine. Pah! How bad can midges be’.
The first night, wild camping on the shore of Loch Lomond, on a hot, overcast, windless night I cried for mercy and a swift death...